package f5

import (
	"database/sql"
	"q5"
)

type DataSet struct {
	rows    *sql.Rows
	columns []string
	values  []interface{}
	numOfReaded int64
	closed bool
}

//已读取函数(调用Next成功的次数)
func (this *DataSet) NumOfReaded() int64 {
	return this.numOfReaded
}

func (this *DataSet) close() {
	if this.rows != nil {
		this.rows.Close()
	}
	this.closed = true
}

func (this *DataSet) Next() bool {
	if this.closed {
		panic("DataSet is closed")
	}
	ret := this.rows.Next()
	if !ret {
		return ret
	}
	this.numOfReaded += 1
	this.GetColumns()
	this.values = []interface{}{}
	for i := 0; i < len(this.columns); i++ {
		str := sql.NullString{}
		this.values = append(this.values, &str)
	}
	err := this.rows.Scan(this.values...)
	if err != nil {
		panic("DataSet Next error:" + err.Error())
	}
	return ret
}

func (this *DataSet) GetColumns() []string {
	if len(this.columns) <= 0 {
		columns, err := this.rows.Columns()
		if err == nil {
			this.columns = columns
		}
	}
	return this.columns
}

/*
   安全版:nil值视为""
*/
func (this *DataSet) GetValues() *[]string {
	values := []string{}
	for _, val := range this.values {
		raw_val := val.(*sql.NullString)
		if raw_val.Valid {
			values = append(values, raw_val.String)
		} else {
			values = append(values, *q5.NewEmptyStrPtr())
		}
	}
	return &values
}

/*
   安全版:nil值视为""
*/
func (this *DataSet) GetByName(name string) string {
	val := this.GetRawValueByName(name)
	if val == nil {
		return ""
	} else {
		return *val
	}
}

/*
   安全版:nil值视为""
*/
func (this *DataSet) GetByIndex(index int32) string {
	val := this.GetRawValueByIndex(index)
	if val == nil {
		return ""
	} else {
		return *val
	}
}

/*
   !!!原始版: 调用方应处理值为nil的情况
*/
func (this *DataSet) GetRawValues() *[]string {
	values := []*string{}
	for _, val := range this.values {
		raw_val := val.(*sql.NullString)
		if raw_val.Valid {
			values = append(values, &raw_val.String)
		} else {
			values = append(values, nil)
		}
	}
	return nil
}

/*
   !!!原始版: 调用方应处理值为nil的情况
*/
func (this *DataSet) GetRawValueByName(name string) *string {
	this.GetColumns()
	for i := 0; i < len(this.columns); i++ {
		if this.columns[i] == name {
			return this.GetRawValueByIndex(int32(i))
		}
	}
	return nil
}

/*
   !!!原始版: 调用方应处理值为nil的情况
*/
func (this *DataSet) GetRawValueByIndex(index int32) *string {
	this.GetColumns()
	sql_val := this.values[index].(*sql.NullString)
	if sql_val.Valid {
		return &sql_val.String
	} else {
		return nil
	}
}

func NewDataSet(rows *sql.Rows) *DataSet {
	dataSet := new(DataSet)
	dataSet.rows = rows
	return dataSet
}